...inside the random mind of the willed man in wheel chair...bursts of simple ups and downs of the struggling life as breathed out on a typical layman's perspective...

February 28, 2013

Blood

Blood
circulates through a system of vessels called arteries and veins. Arteries
carry blood away from the heart; veins carry blood back to the heart. The
average human body has about 5 quarts of blood. Large people may have slightly more;
small people may have slightly less. Every 60 seconds, about 1⁄5 quart of blood
flows out of your heart through your coronary arteries. Sixty seconds after
that, the blood zips through your entire circulatory system and heads back to your
heart.

The
life span of one red blood cell is about 120 days for a man and about 14 days
less for a woman. Men have more red blood cells — about 4.5 to 6.2 million per
cubic microliter of blood compared to 4 to 5.5 million for women. Because males
have more red blood cells, they also have higher values of hemoglobin, the
pigment in red blood cells that carries oxygen throughout the body. They also
have higher levels of iron, an important element in hemoglobin.

White
blood cells play a primary role in your immune system as avengers that zero in
on invaders, such as bacteria, to chew them up and spit them out. The normal
number of white blood cells is exactly the same for men and women — 4,100 to
10,900 per microliter of blood. Blood is a vehicle for nutrients, medications,
and other
circulating particles such as — what a surprise — the lipoproteins that carry
cholesterol.

By
the way, the blood for a cholesterol test always comes from a vein, not an
artery. Blood from a vein is easier and safer to obtain, and it’s a
representative sample of what’s in your body. And yes, clenching your fist does
make your vein pop up so it’s easier to puncture.